USDA-ARS, Beneficial Insects Introduction Research Unit, 501 South Chapel Street, Newark, DE 19713, USA.
J Econ Entomol. 2013 Jun;106(3):1145-54. doi: 10.1603/ec13047.
Tetrastichus planipennisi Yang is a gregarious larval endoparasitoid native to China and has been introduced to the United States since 2007 for classical biological control of the invasive emerald ash borer, Agrilus planipennis Fairmaire, an exotic beetle responsible for widespread ash mortality. Between 2007-2010, T. planipennisi adults (3,311-4,597 females and approximately 1,500 males per site) were released into each of six forest sites in three counties (Ingham, Gratiot, and Shiawassee) of southern Michigan. By the fall of 2012, the proportion of sampled trees with one or more broods of T. planipennisi increased to 92 and 83% in the parasitoid-release and control plots, respectively, from 33 and 4% in the first year after parasitoid releases (2009 fall for Ingham county sites and 2010 for other sites). Similarly, the mean number of T. planipennisi broods observed from sampled trees increased from less than one brood per tree in the first year after parasitoid releases to 2.46 (at control plots) to 3.08 (at release plots) broods by the fall of 2012. The rates of emerald ash borer larval parasitism by T. planipennisi also increased from 1.2% in the first year after parasitoid releases to 21.2% in the parasitoid-release plots, and from 0.2 to 12.8% for the control plots by the fall of 2012. These results demonstrate that T. planipennisi is established in southern Michigan and that its populations are increasing and expanding. This suggests that T. planipennisi will likely play a critical role in suppressing emerald ash borer populations in Michigan.
周氏啮小蜂是一种原产于中国的群居性幼虫内寄生蜂，自 2007 年以来已被引入美国，用于对入侵的绿宝石灰象甲（Agrilus planipennis Fairmaire）进行生物防治，后者是一种外来甲虫，对广泛的灰树死亡负有责任。2007 年至 2010 年，在密歇根州南部的三个县（英厄姆、格拉蒂奥特和希阿瓦西县）的六个森林地点，每个地点释放了 3311-4597 只雌性和大约 1500 只雄性周氏啮小蜂成虫。到 2012 年秋季，在寄生蜂释放和对照区，有一个或多个周氏啮小蜂代的被抽样树木的比例分别从释放后第一年的 33%和 4%增加到 92%和 83%（英厄姆县地点为 2009 年秋季，其他地点为 2010 年秋季）。同样，从释放后第一年每棵树不到一个代的平均值，观察到从抽样树木中观察到的周氏啮小蜂代的平均数量增加到 2012 年秋季的 2.46（对照区）和 3.08（释放区）个代。周氏啮小蜂对绿宝石灰象甲幼虫的寄生率也从释放后第一年的 1.2%增加到释放区的 21.2%，而对照区从 0.2%增加到 12.8%，到 2012 年秋季。这些结果表明，周氏啮小蜂已在密歇根州南部建立，并正在增加和扩大其种群。这表明周氏啮小蜂很可能在密歇根州抑制绿宝石灰象甲种群方面发挥关键作用。
